The appearance of purple spruce needles usually points to root dehydration. If the
damage appears during the winter or early spring, it's probably the result of winter
injury.

All spruce trees, but especially those growing in or near lawns, need water during the
dry fall and winter months. This keeps the needles hydrated and healthy. Other factors can
dehydrate spruce roots and should be considered when diagnosing the problem. For example,
de-icing salts and excess fertilizer can also cause or contribute to the off-color because
they dehydrate roots. A girdled root cuts off or reduces the amount of water reaching the
needles, causing purple needles. Any activity that damages spruce roots (like trenching or
digging) also prevents them from absorbing water well, producing the off-color.